This week's episode of Grey's Anatomy marks Kevin McKidd's directorial debut. The hour will feature the launch of Derek's Alzheimer's clinical trial, Bailey tweeting from the operating room, and the beginning of parenthood for Mark, Arizona and Callie, whose obstetrician will be played by Rachael Taylor.
Meredith wakes to an empty bed. Derek is already at the hospital working on his first Alzheimer's clinical trial. Unfortunately, his first patient is receiving the placebo. Bad luck of the draw. Meredith looks on from the gallery, disappointed, I'm sure, that she's not in the OR.
Meanwhile, Callie reveals her pregnancy news to Mark. He's very excited about them becoming parents. He offers to marry her. "I'm all about raising a baby with you, but there's a line," she says. Mark then remembers how much Lexie is anti-baby. Oops.
While Mark is excited, Arizona is the exact opposite. Not only is she mad that Callie slept with someone else, she slept with a man. "I didn't plan any of this," Callie explains. There's a baby coming, and Callie needs to start getting prepared for that, so Arizona is either in or out. "I'm in," Arizona says begrudgingly. She's still upset, but she'll thaw eventually, right? Right?
While the Chief and Lexie are in surgery, the rest of the doctors in the OR are reading the tweets coming out of Bailey's OR. "What the hell's a Twitter?" the Chief asks. The Chief later finds Bailey and attempts to shut the tweeting down, worrying that it's a lawsuit waiting to happen, but he softens when she accuses him of being inept with technology.
Elsewhere, Jackson and Cristina find themselves fighting over one of Teddy's cases, hoping this will give them a leg up in the race for Chief Resident. Later, they both try to one-up each other by having supreme bedside manner. It's quite hilarious to watch.
Callie decides to give Mark an out, but he's determined to be a father to this child. He just has to tell Lexie first. The real hilarity comes when Arizona reveals the news to Teddy. "I might be having Mark Sloane's baby," she says. "Oh good Lord, he got to you too?" Teddy replies. Arizona weighs the pros and cons and hopes Teddy will convince her to go ahead with the multi-parenting plan.
As Derek prepares for his next patient, Meredith is not happy that Alex is the resident working on the clinical trial. As Derek said before, Meredith clouds his judgment on this matter, so he won't let her work on the trial. Derek's second patient has a wife (portrayed by Lost's L. Scott Caldwell) who is full of questions. Alex isn't as positive in his responses about the trial, which irks Derek.
When Callie thinks she may be having a miscarriage (oh no, not that again), she goes to see the new obstetrician, Lucy Fields. Mark questions her credentials, and in turn Lucy questions who the hell they all are. "Lesbian lover, baby daddy," Callie says, pointing at the two. The family threesome gets a first glimpse at the baby, and Lucy says their kid is fine.
When Derek and Alex's patient starts freaking out and screaming for his wife, Alex points her out, but Daniel says that it's not her. Meredith, quick on her feet when it comes to Alzheimer's patients, calms him down. Victoria, who Daniel was screaming for, is another patient in the home he lives in. The pair is reunited as their respective loved ones detail the relationship to the doctors. When each is lucid, they know who their real lovers are.
When Bailey breaks the news that they can't tweet, Lexie stands up for their followers, saying they can't hold back all this information now. Bailey caves, knowing that the Chief will probably never find out.
Teddy's patient also has a freak out, not wanting to have the surgery because of the five percent chance of dying. She doesn't want to end up in a home or be a burden on her family, but Cristina convinces her to do the surgery. While Teddy is deciding who will be in the OR, Jackson uses Cristina's past OR breakdown as an insult. Meredith tracks Cristina down to comfort her, but Cris was just fake crying so she could send Jackson on a wild goose chase to find Owen, who is actually at the dentist.
Two hours later, Callie is still in the patient room. She won't leave, fearing for the baby's safety. Following more tests, Callie sends Mark a 911 page. He, too, has a freak out since she just paged him because she's scared and full of hormones. Callie feels like it will all turn into a disaster, that if she even moves the wrong way, she'll lose the baby. Lucy runs some super-specific tests on the baby just to find the heartbeat, which she knows will calm Callie down.
In the one scene that Kevin McKidd actually appears in, he helps the Chief figure out Twitter, which means Bailey is busted. He storms in the OR, and Bailey plays dumb. When the patient starts to bleed out, Lexie continues to furiously tweet. Using some of the "@ replies" that come back, the Chief and Bailey are able to figure out how to save the patient. While Bailey is off at a different hospital, the Chief finally gets into the Twitter business with April and Lexie, who is tweeting out different medical facts and stories from the Chief.
Sadly, Derek and Alex's patient receives the placebo, meaning his wife will most likely lose her husband. Alex is gutted, especially when Daniel asks for Victoria immediately following the surgery. He encourages the wife to stand by Daniel's side because he'll need all the help he can get in the coming months. Derek is pleased with how Alex handled that, but Alex decides to leave the trial. He suggests Derek let Meredith in on the trial, but also that Derek should put in a good word for Alex in the Chief Resident race.
At the end of the day, Arizona starts moving Callie's stuff back in the apartment. Callie initially protests, but Arizona finally stands up and says they're back together and they're going to raise this baby together. Love it.
Across the hall, Lexie cooks dinner for Mark, and he blurts out that Callie is pregnant. Lexie quickly figures out that Callie and Mark slept together. He pleads for her to understand that he wants to raise this child, but she decides to storm out amidst yelling: "How the hell did you get me in this position twice?"
The episode closes on Derek telling Meredith to put her name on the OR board for the clinical trial. Aw, husband and wife together again.
What did you think of the Kevin McKidd-directed episode? Do you think Callie, Mark and Arizona can make this parenting thing work? Will Derek's trial be successful? How long before the Chief gets his own Twitter handle? And what should it be called? Discuss all that and more in the comments below!